Conclusion
Among all tested nitrogen sources at optimized condition,
the most efficient in improving ethanol productivity in fermentation of enzymatically hydrolyzed hilly red potatoes
by Saccharomyces cerevisiae, isolated from brewer’s yeast
was 2% of ammonium sulphate. Positive effects were
obtained with all added nitrogen sources indicating that
exogeneous nitrogen source is necessary for improved
viability of yeast cells and thus the productivity rate of
ethanol.